Combine the butter, salt and 1 cup water in a medium saucepan over low heat, stirring until butter has melted. Bring mixture to a boil, then remove pan from heat. Add the flour all at once and beat vigorously with a wooden spoon until dough comes together in a mass. Return pan to stove and, over medium heat, continue to beat dough for another minute until a thin film appears on bottom of pan.

Scrape dough into bowl of a stand mixer and beat on medium speed for 1 minute to cool it a bit. Before adding the beaten eggs, reserve about 1 tablespoon egg for glaze. Add eggs in 4 increments, letting each addition absorb completely into dough before adding next. Mixture may look sloppy but will magically come together in a very thick batter. (If you feel in need of a workout, beat eggs in by hand.)

Add 3/4 cup of the cheese, reserving rest for garnish. Beat in cheese with the mustard and pepper until well-blended.

Drop by tablespoonfuls, about 1 inch apart, onto parchment-lined baking sheets or use a pastry bag to pipe 1-inch mounds onto baking sheet. Using fingertip or a pastry brush, lightly coat top of each puff with some reserved egg.

Bake in preheated oven for 20 minutes, then reduce heat to 350 F and bake for 10 to 15 minutes longer until golden-brown. Immediately top each gougere with a few strands of reserved cheese. Return pans to oven to "set" cheese; it should take less than a minute. Serve warm. Gougeres can be baked, then frozen in plastic freezer bags for up to a month. When you're ready to reheat, place them frozen on baking sheets at 325 F for 5 minutes.

Makes about 36 small puffs.

— Recipe adapted by the Minneapolis Star Tribune from "The Art & Soul of Baking" from Sur La Table.